Spectacles with supplemental lenses

ABSTRACT

A pair of spectacles is provided with supplemental lenses which are mounted on arms supported on the bridge connecting the primary lenses of the spectacles. The arms are mounted on the bridge by a clip mounted on the bridge by a screw engaging the end portions of a clamping loop extending around the bridge. The supplemental lenses may be binocular loupes which are attached to the bridge via relatively flat cross arms that are flat in a direction transverse to the primary lenses so that there is no substantial obstruction of the primary lenses.

The present invention relates to a fixing assembly, capable of fittingspectacles with supplemental lenses which serve as filters, protectiveshields and/or magnifying glasses over a restricted sub-area of theactual lenses. The fixing assembly includes mechanical holders whichenable the positioning, aligning and/or maintaining the alignment ofsupplemental lenses.

For example, the dentists have a need to wear a protective shield forblocking the radiation of a UV-curing device from striking directly onthe eyes. A separate UV-protection shield held by a dental assistant isinconvenient to use. In addition to UV-radiation, the protection can beapplied to any ophtalmologically harmful radiation. In addition, theseparate lenses may also serve as filters for making certain objectsmore clearly detectable.

On the other hand, it is often desirable that the spectacles be providedwith a magnifying sub-area that can be used in precision work whichrequires magnification from time to time. Manufacturing special bifocalglasses for this purpose is expensive.

A fixing assembly of the invention can also be used for fitting thespectacles with binocular loupes, comprising an attachment frame and twoloupes, each provided with at least two lenses of which the ocular lenscloser to the eye is smaller than the outer objective lens.

Such binocular loupes to be attached to spectacles are intended tofacilitate precision work, such as the work of a dentist or of aprecision mechanician. The drawbacks of prior art binocular loupesinclude a complicated design and an excessive weight as well as arestricted field of vision caused by the loupes. U.S. Pat. No. 5,182,588anticipates the attachment of a protective coating to the surface ofspectacle lenses over a restricted sub-area of the lens. A thin surfacecoating is difficult to manufacture and it alters the spectaclespermanently and, thus, the solution is poorly adaptable to spectaclesadjusted to each individual's own eyes. Furthermore, the coating formedby a thin layer is difficult to provide with a sufficient protectiveeffect if clear transparency is desired at the same time. The coatingonly offers protection and does not provide a possibility of usingsimultaneously or alternatively a magnifying glass or a binocular loupe.

Moreover, e.g. U.S. Pat. No. 4,647,165 and U.S. Pat. No. 3,446,548disclose the placement of various supplemental lenses over a sub-area ofthe actual lenses by means of mechanical, adjustable arms. These priorart solutions do not afford a reliable attachment for supplementallenses and the attachment arrangement is not suitable for all types ofspectacles. The attachment is often secured by manufacturing speciallydesigned spectacles, leading to a substantial increase in total costs.The most general drawback in prior art attachment units based onmechanical attachment arms is the fact that the attachment assembliesobscure and interfere with the field of vision.

An object of the invention is to provide a fixing assembly forattachments mountable on the user's own spectacles, said assembly beingas inconspicuous, easy to use and economically priced as possible andversatile in applying it to fixing various attachments. In theattachment of binocular loupes, for example, it is important that thefixing assembly and the loupes screen as little as possible of the fieldof vision, whereby the view can be readily directed past the loupes atthe same target that has just been examined and magnified through theloupes.

A particular object of the invention is to provide a fixing assembly forsupplemental lenses and/or binocular loupes, which is suitable for usein connection with many different types of spectacles.

These objects are achieved on the basis of the characterizing featuresset forth in the annexed claim.

For example, the use of resiliently flexible arms offers substantialbenefits if compared to rigid hinged frames. The lenses carried byflexible arms are readily cleanable and return to the original positionthereof.

Other embodiments of the invention assist in the individual focusing ofloupes for setting the loupes precisely according to the ocular gap of auser and for minimal screening of the field of vision caused thereby.

The invention will now be described in more detail with reference madeto the accompanying drawings, in which

FIG. 1 is a frontal view of a fixing assembly of the invention forattaching supplemental lenses to spectacles;

FIG. 2 shows in a larger scale the attachment between a supplementallens and its holding arm;

FIG. 3 is a larger-scale side view of a supplemental lens attachmentclip and the setting of a supplemental lens 4 relative to a spectaclelens. The figure also depicts the attachment of a separate magnifyingglass 16 by means of the same metal clip;

FIG. 4 is a plan view of a metal clip included in the fixing assembly ofFIG. 3;

FIG. 5 is a section along a line V--V in FIG. 4;

FIG. 6 is a section along a line VI--VI in FIG. 4;

FIG. 7 is a plan view of a fixing assembly of the invention forattaching loupes to spectacles;

FIG. 8 is a frontal view of the binocular loupes shown in FIG. 7;

FIG. 9 is a side view of the same binocular loupes; and

FIG. 10 is a more detailed view of loupe attachment arms with theirhinges and adjustment facilities.

The fixing assembly for attaching supplemental lenses will be firstdescribed with reference made to FIGS. 1-6.

Supplemental lenses 4 protecting from ophtalmologically harmfulradiation and/or serving as magnifying glasses and/or as filters arepositioned on the inside surface of actual lenses 1 adjacent to thebottom edge of the lenses 1. Attachment of the supplemental lenses 4 iseffected by means of resiliently flexible arms 5, comprising e.g. steelwire. The bottom ends of said arms 5 are fixed by means of an adhesivein a slot made in the bottom edge of the supplemental lenses 4. The topends of said arms 5 are secured to a metal clip 6 that can be tightenedwith a screw 7. The metal clip 6 is in engagement with a bridge 3connecting rims or eyewires 2 of the actual lenses across the nose. Themetal clip 6 includes two body members 8, 9 for clamping the ends of thearms 5 therebetween by tightening the screw 7. A clamping hook 10 madeof a flexible, soft metal, e.g. silver provides a gripping yoke aroundthe bridge 3. The ends of said clamping hook 10 are received in a hole11a, 11b, extending through the body members 9, 8 and dimensionedrelative to the screw 7 such that the screw threads engage with thematerial of the clamping hook 10. The clamping hook 10 can be providedwith existing threads or those may be a result of cutting by the screw.Such a clip assembly makes it possible that a single screw 7 be used forclamping the clip securely to the bridge 3 and at the same time forpressing the arms 5 into the engagement with the clip. The surface ofsaid clip body member 8, facing the other body member 9, is providedwith grooves 12 less deep than diameter of the arms 5 for receiving saidarms 5. Thus, the arms 5 retain the alignment thereof and, prior tofinal tightening of the screw 7, the length of the arms 5 can beregulated by a longitudinal adjustment thereof between the body members8, 9 for placing the supplemental lens 4 in a proper position. Finally,the extra length from the top ends of the arms 5 can be cut off. If thearms cannot be fixed from below, it can be done from above by bendingdown the arms extending from the top edge of the clips.

In addition, the body member 8 of the clip 6 is designed for anengagement with a yoke-like holder 14 mounted on the base of an arm 15supporting a separate magnifying and/or protective glass 16. Theyoke-like holder 14 is pressed from above on top of the body member 8with ribs included in the inner surfaces of the yoke 4 engaging grooves13. This type of magnifying glass 16 in association with spectacles isprior known but, according to the invention, it is attached in a newfashion by means of a lightweight holder yoke 14 to a metal clip 6 ofthe invention.

FIG. 2 shows in more detail the possibility that the bottom half of asupplemental lens 4 comprises a protective glass 4b and the top half amagnifying glass 4a. In this case, a separate magnifying glass 16 is notneeded. Alternatively, either one of the magnifying glasses 4a or 16 canbe a filter or a combination of a filter and a magnifying glass.

The following description deals with the exemplary embodiment shown inFIGS. 7-10.

Binocular loupes 18 are fastened by means of a bracket 17 to a nosebridge 3 included in spectacles. Each loupe 18 is fitted with at leasttwo lenses of which the ocular lens closer to the eye is smaller thanthe outer objective lens. As for its outer surface, a loupe jacket 19connecting the lenses also diverges at a sector angle which isessentially consistent with that drawn from the pupil to the rim of theocular lens. Thus, restriction of the field of vision caused by theloupes is minimal. The user is able to look through or past the loupesaccording to his or her choice by just slightly turning the viewingdirection and the head.

The loupe jackets 19 may consist of tubes having a thin wall thicknessand a conicity which is consistent with said sector angle. The loupejacket material may be a metal, fiber-reinforced plastics etc. The loupejacket may have a cross-section which is circular, elliptical orpolygonal.

The loupes 18 are mounted on flat crossarms 20 which can be bent athinge points 21 that are made of a metal and have a shape which changesas a result of bending. The hinge points 21 can be made of a materialother than the arms 20, e.g. wire threads embedded in the arm materialwhich is e.g. light metal or fiber-reinforced plastics. The axialdirections of hinges 21 are selected so as to control bending of thearms 20 such that, in various positions of the loupes 18, the centreaxes thereof cross each other at essentially the same distance from thebinocular loupes 18. Thus, the loupes always remain on focus providedthat the distance between the loupes is set according to the distancebetween the eyes.

At the mid-point thereof between the hinges 21, said crossarms 20 areconnected to a lengthwise arm 24 whose attachment point is also providedwith a hinge 22 made of a resilient metal. The arm element 24 isprovided with a lengthwise slot 28 and the arm element 26 with acrosswise slot 27 and, thus, attachment of the arm elements 26 and 24 toeach other by means of a screw 25 affords both a lengthwise andcrosswise adjustment. The arm element 26 is connected with a hinge 23 toa yoke-like clip 6a which is mountable from above (or from below) on ametal attachment body 6b, having its sides provided with grooves 6c andthe inner surfaces of the yoke 6a being shaped accordingly. In thiscase, the members 6a and 6b together provide an attachment clip,generally designated by reference numeral 6. With this snap-fitcoupling, the binocular loupes are readily removable and replaceable.The small-sized and inconspicuous attachment body 6b can be permanentlyfixed to the nose bridge 3 of spectacles. The attachment body 6b can befixed to nearly all types of spectacles by using a clamping hook 10,made of a soft metal and constituting a loop which grips around the nosebridge 3 and whose ends are received in a hole extending through theattachment body 6b and dimensioned identically to the hole in the member8 in FIG. 6, i.e. in such a manner that the threads of a screw 7 engagewith those of the clamping hook 10. Such a clip is small, inconspicuousand firm and adaptable to nearly all types of spectacles.

What is essential about the invention is that the fixing assembly andthe loupes are lightweight and only obscure a small section of the fieldof vision. This objective can be favored even further by designing athin-walled loupe jacket so as to comply with the sector angle of afield of vision covered by a small-sized ocular lens. In addition, theflat shape and positioning of attachment arms are selected so as tointerfere minimally with the field of vision. At the same time, however,the attachment arms, with the aid of their hinge points, enable anindividual alignment and setting of the distance between the eyes, suchthat the loupes have a focus always fixed in position. The loupes mayhave a length of e.g. 20-30 mm. The ocular lens may have a diameter ofe.g. about 10 mm. The ocular lens' distance from the eye is in the orderof 20 mm when the lens is positioned very close to the lens ofspectacles. The objective has a diameter which is determined by thesector angle and the length of the loupes.

I claim:
 1. A fixing assembly for attaching supplemental lenses tospectacles having primary lenses connected by a bridge, said fixingassembly comprising a clip having a clip body on one side of said bridgeand a clamping hook extending from said clip body around said bridge,said clamping hook having a pair of end portions received within saidclip body, a pair of arms extending from said clip body, saidsupplemental lenses being mounted on said arms, and a screw extendinginto an opening in said clip body and threadedly engaging each of saidend portions to thereby tighten said clamping hook about said bridge assaid screw is advanced relative to said end portions.
 2. The assembly asset forth in claim 1 wherein said arms are flexible and resilient. 3.The assembly as set forth in claim 2, wherein the clip includes a pairof members, said arms having ends clamped between said members.
 4. Theassembly as set forth in claim 1, wherein the arms have opposite ends,one end of each arm being attached to an edge of a corresponding one ofthe supplemental lenses and the other end of each of the arms aresecured by said clip.
 5. The assembly as set forth in claim 1, whereinthe clip is made of metal.
 6. The assembly as set forth in claim 1,wherein the clip body engages a yoke-like holder mounted on an armsupporting a separate supplemental lens.
 7. The assembly as set forth inclaim 1, wherein the supplemental lenses are supported between theprimary lenses and a wearer of the spectacles and of adjacent to abottom portion of the primary lenses.
 8. The assembly as set forth inclaim 1, wherein the supplemental lenses are a pair of binocular loupes,each binocular loupe including at least two pair of binocular lenses,one of the binocular lenses being a smaller inner ocular lens and theother lens being an outer objective lens; said ocular having a rim, aloupe jacket connecting the binocular lenses, said loupe jacketdiverging along line a sector angle which is substantially the same asthe sector angle drawn from the pupil of an eye of a wearer to the rimof the ocular lens, the arms attaching the loupes to the clip body, saidarms being flat in a direction transverse to the primary lenses, wherebythe arms do not substantially obstruct the primary lenses.
 9. Theassembly as set forth in claim 8, wherein the loupe jackets areconcentric with said sector angle, the loupes being attached tocrossarms extending from the spectacles, said crossarms being foldableat hinge points made of a metal deformable upon bending.
 10. The fixingassembly as set forth in claim 9, wherein said loupes have center axes,said hinge points controlling the folding of said crossarms to maintainthe crossing of the center axes of the loupes at substantially the samedistance from the loupes regardless of the angle of the arms.
 11. Thefixing assembly as set forth in claim 9, wherein the crossarms areconnected to a central arm which is provided with a folding hinge and anadjustment permitting movement of the crossarms toward and away from theprimary lenses.
 12. A pair of spectacles for use by a wearer including apair of primary lenses and a pair of secondary lenses supported over theprimary lenses, a bridge connecting the primary lenses, said secondarylenses being a pair of binocular loupes, each binocular loupe includingat least two binocular lenses, one of the said at least two binocularlenses being an inner ocular lens and the other binocular lens being anouter objective lens; said ocular lens having a rim, a loupe jacketconnecting the binocular lenses, said loupe jacket diverging along asector which is substantially the same as a sector drawn from the pupilof an eye wearer to the rim of the ocular lens, said binocular loupesbeing attached to the spectacles by attachment arms, said attachmentarms being flat in a direction transverse to the primary lenses wherebythe secondary lenses do not substantially obstruct the primary lenses,the loupe jackets being concentric with said sector, said attachmentarms being crossarms extending from the spectacles, said crossarms beingfoldable at hinge points made of a deformable metal to permit bending.13. The assembly as set forth in the claim 12, wherein said loupes havecenter axes, said hinge points controlling the folding of said crossarmsto maintain the crossing of the center axes of the loupes atsubstantially the same distance from the loupes regardless of the angleof the arms.
 14. The assembly as set forth in claim 12, wherein thecrossarms are connected to a central arm which is provided with afolding hinge, and an adjustment permitting movement of the crossarmstoward and away from the primary lenses.